The poll promise, made in Shepparton with federal Opposition Leader Bill Shorten, follows the Abbott government's rejection of a $25 million plea from Coca-Cola Amatil, SPC Ardmona's parent company, for investment in the plant. That $25 million could have triggered a further $25 million from the Victorian government, and then spurred up to $161 million in investment from Coca-Cola Amatil in the plant and facilities.

If SPC Ardmona closes, there are fears up to 3000 jobs will go, driving up unemployment in an area already struggling with a high jobless rate.

Labor's $30 million plan is a co-investment that the party says will assist the company to buy new equipment and up-skill workers to help expand its markets.

''This is not a handout, it is not a bailout, it is a partnership,'' Mr Andrews said.

''This company and the thousands of jobs that rely on it are too important to lose. Time is running out and it's now up to Denis Napthine to match our offer and support this company and the thousands of workers and growers.''

Last Friday, Dr Napthine said the government was working on a ''plan B'' to help the company, and on Monday, departmental officials were meeting with the company. Dr Napthine and senior ministers are set to meet the company this week.

SPC welcomed Labor's pledge. Last week, the company said alternative plans for SPC would require a review, with further announcements from the board due on February 18.

Victorian Treasurer Michael O'Brien accused Labor of grandstanding, refusing to match Labor's $30 million offer. ''We're certainly not going to commit a blank cheque without a plan attached, which is what Labor has done today. It's typical Labor fashion to spend money you don't have and ask questions later,'' he said.

Mr O'Brien said they would consider offering more cash after further discussions with SPC, on top of the $4.4 million offered last year.

Mr Shorten lashed the Abbott government for scapegoating SPC workers by highlighting leave and shift loadings in employees' workplace agreements.

Treasurer Joe Hockey said conditions available to workers in their contracts were ''astounding'', and that it would not have been the proper use of taxpayers' money to hand $25 million to the fruit processor.

But Mr Shorten said the 1600 workers at SPC, including 500 on the payroll full time, appeared to have missed out because Shepparton was a safe Liberal seat.